Does anyone know of any games on PC that help you learn music theory or keyboard/piano? Or any other instrument for that matter?

I've heard about Rocksmith for guitar but I'm not sure how well it actually helps you learn to play?

But there seems to be very few games that teaches you about scales, chords or composition.

Any ideas?

 

I love rocksmith, you can use a real guitar to play the songs.

 

That's harmony theory.

Indeed I don't have knowledge of any GAME that theaches musical theory, maybe just practice, however you can find tons of apps (mobile or pc) that are good quick REFERENCE guides for scales and/or theory (e.g Piano Companion for android), plus there are other apps that can help with relative/absolute pitch, like Earmaster.

However, you have to follow courses to learn theory, (and there are tons, free or not), search in YT if you don't want to spend time in reading.

For practice, see post above, Synthesia or Simply Piano are pretty consolidated and valid apps.